Network Power Switches

You can fence GFS nodes with power switches and fencing agents available with Red Hat Cluster Suite. For more information about fencing with network power switches, refer to Configuring and Managing a efore you install and set up GFS, note the following key characteristics of your GFS file systems:

Number of file systems

Determine how many GFS file systems to create initially. (More file systems can be added later.)

File-system name

Determine a unique name for each file system. Each file-system name is required in the form of a parameter variable. For example, this book uses file-system names gfs1 and gfs2 in some example procedures.

Journals

Determine the number of journals for your GFS file systems. One journal is required for each node that mounts a GFS file system. Make sure to account for additional journals needed for future expansion.

GFS nodes

Determine which nodes in the Red Hat Cluster Suite will mount the GFS file systems.

GNBD server nodes

If you are using GNBD, determine how many GNBD server nodes are needed. Note the hostname and IP address of each GNBD server node for setting up GNBD clients later. For information on using GNBD with GFS, see the Using GNBD with Global File System document.

Storage devices and partitions

Determine the storage devices and partitions to be used for creating logical volumes (via CLVM) in the file systems.Red Hat GFS is a cluster file system that is available with Red Hat Cluster Suite. Red Hat GFS nodes are configured and managed with Red Hat Cluster Suite configuration and management tools. Red Hat GFS provides data sharing among GFS nodes in a Red Hat cluster. GFS provides a single, consistent view of the file-system name space across the GFS nodes in a Red Hat cluster. GFS allows applications to install and run without much knowledge of the underlying storage infrastructure. GFS is fully compliant with the IEEE POSIX interface, allowing applications to perform file operations as if they were running on a local file system. Also, GFS provides features that are typically required in enterprise environments, such as quotas, multiple journals, and multipath support.

GFS provides a versatile method of networking your storage according to the performance, scalability, and economic needs of your storage environment. This chapter provides some very basic, abbreviated information as background to help you understand GFS. It contains the following sections:

5. Recommended References

For additional references about related topics, refer to the following table:

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